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Global Range: Chiefly coastal plain, North Carolina south to Florida and west to Alabama and in Mississippi Embayment to southern Missouri and Arkansas. Very scattered distribution. Devall et al. (2001) note the possibility that the species never occurred in present-day Florida - the only evidence for occurrence there are two 1800s specimens labeled "Florida" and "West Florida"; however, the "West Florida" territory of that time includes parts of present-day LA, MS, AL, and FL. Known county distribution is as follows: North Carolina - Cumberland, Sampson, Onslow, and Bladen (historical) counties; South Carolina - Beaufort, Berkeley, and Colleton (historical) counties; Georgia - Baker, Calhoun, Effingham, Taylor, Wheeler, Worth, Chatham (historical), and Screven (historical) counties; Florida - Gadsden (historical) County; Alabama - Covington and Wilcox (historical) counties (Covington County locations were found in 2004, representing a re-discovery of the species in Alabama); Mississippi - Bolivar, Sharkey, Sunflower, and Tallahatchie counties; Louisiana - Union (historical) and Morehouse (historical) parishes; Arkansas - Ashley, Clay, Craighead, Jackson, Lawrence, Poinsett, and Woodruff counties; Missouri -Ripley County; re-introduced population in Butler County. A single range extent polygon was calculated as approximately 500,000 square km using GIS tools, but if various groups of populations were all considered "disjunct" from one another, range extent could be considerably less than this.

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Diagnostic Description

Lindera melissifolia (and L. benzoin) can be distinguished from another rare species, L. subcoriacea, by its thin leaves that are not strongly whitened below. L. melissifolia can be distinguished from the common L. benzoin by leaves that are drooping, as opposed to erect-ascending or spreading, have a much stronger sassafras odor, and have more rounded bases. L. melissifolia also tends to occur in wetter habitats than does L. benzoin (Delay et al. 1993).

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Ecology

Habitat

Comments: Can apparently occupy a variety of habitats as long as hydrological requirements are met. Occurs in seasonally flooded wetlands such as floodplain/bottomland hardwood forests and forested swales, on the bottoms and edges of shallow seasonal ponds in old dune fields, along the margins of ponds and depressions in pinelands, around the edges of sinkholes in coastal areas with karst topography, and along the borders of Sphagnum bogs. Usually in shade, but tolerates full sun.

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Population Biology

Number of Occurrences

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 21 - 300

Comments: Approximately 99 extant occurrences are currently mapped, of which 2-3 are reintroductions (2 in Missouri and possibly 1 in Arkansas). An additional 17 occurrences are likely extirpated. However, the true number of extant populations may be less than 99, as some currently-mapped occurrences are in close proximity. For example, 19 EOs in Mississippi derive from one USFS inventory of the Delta National Forest, and 18 EOs in Arkansas derive from one status survey in Jackson and Lawrence counties. If more data on these occurrences were available, perhaps they could be delineated as a smaller number of populations.

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NatureServe Conservation Status

Reasons: Mapped and believed extant at about 99 sites, although some of these are in close proximity, so the number of extant populations may be somewhat less. A few extant populations appear quite large, but may contain few different genetic individuals; many sites are small and isolated. Believed extirpated from Louisiana and possibly Florida; extant populations are known from the coastal plain in North Carolina south to Georgia and Alabama and from the Mississippi Embayment in Mississippi, Arkansas, and Missouri. Extensive clearing and drainage of bottomland forests tis probably the major factor affecting the species, both historically and currently. Also appears susceptible to the emerging Red Bay or Laural Wilt disease; one Georgia population is known to be infected, but the full potential range and impact of the disease is unknown at this time. Limited sexual reproduction, dispersal, and recruitment are also a concern for the species' persistence in its now highly-fragmented habitat.

Environmental Specificity: Narrow. Specialist or community with key requirements common.

Comments: Needs closed canopy and standing water during some part of the year.

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Trends

Comments: Several site extirpations have been documented in the past 30 years, due to factors such as agricultural conversion and land clearing. For example, Richards and Orzell (1987) noted that "many small populations [in Arkansas] have been damaged or destroyed since 1970." Nevertheless, at least some reasonably large populations appear stable. For example, after three years of monitoring, populations in Bolivar County and Delta National Forest, MS did not appear to be declining; in addition, the natural Missouri population studied in 1983 was surveyed again in 1998-1999 and did not appear to have declined (Devall et al. 2001) and still appears to be stable (T. Smith, pers. comm. 2008). Overall, Devall et al. (2001) felt that the species' rangewide status "will [continue to] decline without human intervention."

Global Long Term Trend: Decline of 30-70%

Comments: This species has probably always been [relatively] rare (Devall et al. 2001). Nevertheless, occurrences of the habitat types in which it is known to thrive have been greatly reduced in number and quality in recent and historic times (USFWS 1985). When this species was proposed for Federal listing in 1985, the US Fish and Wildlife Service noted that "almost all populations known in 1985 had declined since their discovery, some severely." Rangewide, 17 occurrences are thought to be extirpated.

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Threats

Comments: Loss and alteration of habitat has been and continues to be the most significant threat. Multiple causes of habitat loss/degradation are known, including land clearing, hydrological alteration (drainage, ditching, flooding), timber harvesting, leveling of mound/depression topography, and road building. Uses to which habitats have been converted include tree farming (plantations), crop production, and residential areas. The reduced area and extreme fragmentation of remaining suitable habitat is of concern, especially given incomplete knowledge of the effects of surrounding land practices and the potential impact of climate change (P. McKenzie pers. comm. 2008). Fragmentation also greatly reduces the chances that waning populations will be rescued or replaced by incoming propagules. An important emerging threat to this species is Red Bay or Laural Wilt disease. This fungal disease, spread by a newly-established ambrosia beetle from Asia, is causing widespread mortality of red bay (Persea borbonia) trees in coastal SC, GA, and FL so far and is spreading rapidly north, south, and inland. This disease can infect Lindera melissifolia as well (Johnson et al. 2007). One L. melissifolia stand in Effingham Co., GA is under attack; it has not yet fully succumbed and is being monitored (T. Patrick, pers. comm. 2008). It is possible that this disease could spread throughout the range of L. melissifolia. Threats of lower magnitude include trampling by domestic animals such as hogs and cattle (affects at least one GA site and one AR site), competition with aggressive non-native plant species, and increased frequency of droughts in the southeast. Less severe dieback of plant stems than that caused by Red Bay disease has also been observed at many sites throughout the range, but it has proven difficult to conclusively link stem dieback to population decline. Overall, threats remain high in most of the range.

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Relevance to Humans and Ecosystems

Risks

Stewardship Overview: Given the species' habitat requirements and ecology, Kral (1983) believed that selective logging of the swamp hardwood overstory might be compatible with population persistence. However, he cautioned that clear cutting could raise flood levels beyond the species' tolerance, and that drainage of occupied sites would almost certainly eliminate the species. Devall et al. (2001) believed that full recovery of this species would require establishment of new populations. They noted that clonal propagation appears to be an efficient way to generate plants for transplantation without damaging the original clones.

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Wikipedia

Lindera melissifolia

Lindera melissifolia, common name Pondberry or Southern Spicebush, is a stoloniferous, deciduous, aromatic shrub in the laurel family. This endangered species is native to the southeastern United States, and its demise is associated with habitat loss from extensive drainage of wetlands for agriculture and forestry.[2][3] Restoration efforts are currently being conducted.

Contents

Form: Pondberry occurs in dense thickets with erect or ascending shoots up to 2 m tall and few branches; stems are connected underground by stolons. Thickets of female plants tend to be smaller than those of males and are sometimes absent from populations.[4] Die-back of stems is a fairly common occurrence.

Foliage: The drooping, alternate leaves are oblong-elliptic to narrowly ovate, 5–16 cm long, 2–6 cm wide, and tend to be strongly tapered to a point at the tip.[5] Undersides are strongly net-veined and covered with short, soft hairs. When crushed, the leaves strongly resemble sassafras (Sassafras albidum) in fragrance.[3] Foliage is deciduous.

Flowers: Stems flower after 2 to 4 years of growth.[6] Male and female flowers, each 5–6 mm across, are produced on different plants (dioecious).[4] Flowers appear before the leaves (February to mid-March) in tight, stalkless clusters. The petal-like tepals are pale to bright yellow, oblong, and 2 mm long. Male flowers occur in dense clusters, with 9-12 stamens surrounded by two whorls of tepals. Female flowers are less conspicuous, with fewer flowers per cluster and a single pistil surrounded by two whorls of tepals; the outer whorl is petal-like and the inner whorl is reduced to nectar-producing scales. Flowers remain open for about 1 week making thickets conspicuous.[2] Flowers are thought to be insect pollinated.[6] Late season frosts occasionally damage flowers, resulting in reduced fruit set.

Fruit: A bright red, single-seeded drupe, ellipsoid, 10–12 mm long matures in late summer or fall (August to early October). Individual fruit stalks are 9–12 mm long, 2.5-3.0 mm thick, and appear swollen at the apex. Stalks persist beyond fruit fall; their presence indicates the plant's sex and past level of fruit production. Fruit production is highly variable from year-to-year, ranging from 0 to 150 fruit per stem.[2]

Pondberry occurs in shallow depression ponds in wetland habitats with hydric soils, along margins of cypress ponds, and in seasonally wet, low areas among bottomland hardwoods. At present there are some 36 populations in Alabama, Arkansas, Georgia, Mississippi, Missouri, North Carolina, and South Carolina.[7] It has apparently been extirpated from Louisiana and possibly Florida. Most of these populations are located in Lower Mississippi Alluvial Plain, with the largest population being in the Delta National Forest in western Mississippi.

Pondberry has probably always been a rare species, and knowledge of its ecology is limited.[6] In Mississippi, pondberry occurs in bottomland hardwood forests. In northeastern Arkansas and southeastern Missouri pondberry is found on the bottoms and edges of shallow seasonal ponds in old dune fields, but in southeastern Arkansas it occurs in low habitat along a river. In South Carolina the species occurs in areas with karst topography, around the edges of sinkholes, and in Georgia it occurs along the borders of sphagnum bogs. Sunlight at the different sites ranges from deep shade to almost full sun. Most pondberry colonies occur in light shade beneath a forest canopy, but a few grow in almost full sunlight. Pondberry appears to be able to occupy widely different habitats as long as its requirements for water are met. In open conditions, competition from other plant species may be a problem.[6]

Many of the remaining populations consist only of male plants and are apparently the sprouts of a single individual. Habitat fragmentation severely affects dioecious species like pondberry because populations with plants of a single sex can only vegetatively reproduce. With significant habitat loss, plants become ever more isolated, lessening the likelihood that pollinators will travel from male to female plants.[5]

Clones expand vegetatively through stolons, and this mechanism of vegetative reproduction is the principal way that colonies develop. Stems usually live 6 or 7 years, and when a stem dies it is usually replaced by a new stem that grows from the base of the plant.[3] Thus, mature colonies often include some dead stems intermingled with numerous live stems.

Despite the regular production of mature fruit, virtually no seedlings of pondberry have been observed at any of the known sites.[6] The cause of this apparent lack of natural reproduction is not currently known, but the consequences are clear—it severely reduces the species' chance for long-term survival. Sexual reproduction of pondberry is critical for long-range dispersal and genetic diversity.

Before modern flood control was imposed along the Mississippi River and its tributaries, historic floods may have been an important mechanism in fruit and/or seed dispersal over long distances or for creating suitable conditions for seedling establishment. Although the fruit of pondberry sinks in water after a short time, the seed with the pulp removed will float for a day or sometimes longer.[8]

Characteristics of pondberry's fruit—the showy color, fleshy pulp, and its persistent on stems—suggest that animals, particularly birds, may be important dispersal agents. Of 82 bird species observed in the vicinity of pondberry thickets in fruit, only two species were observed to eat the fruit—hermit thrushes (Catharus guttatus) and northern cardinals (Cardinalis cardinalis).[8] Of these, the cardinals destroyed the seed by crushing and is thus considered a seed predator. However, the hermit thrush swallows the whole fruit and later regurgitates the seed, indicating that it is an important seed disperser. The foraging habits of the thrush suggests that most of the seeds would be dispersed with 100 m of existing female colonies. Mammals may also be potential dispersers of pondberry seeds, including the raccoon (Procyon lotor) and opossum (Didelphis virginiana).[8] Historically, the black bear (Ursus americanus) may have been important to seed dispersal.

Seed germination does not appear to be a deterrent to seedling establishment. Fairly high rates of germination have been reported under both controlled and field conditions.[9][10] Removal of the fruit's pulp and sowing seeds into the soil favor germination. Under field conditions, germination of sown seeds has been observed to occur over a number of years suggesting some form of dormancy.[11]

The artificial establishment of pondberry to new areas may be needed if the species is to recover. Plants have been successfully transplanted from existing colonies to suitable locations. The transplants seem to do well in some locations although survivorship and growth has been low in others.[11][12] Both transplants and seedlings do well under cultivation in a nursery setting, which has been used to provide planting stock for creating new colonies in field locations.

The spicebush swallowtail (Papilio troilus) larvae feed on the leaves and roll themselves in a leaf making a tent. Leaf cutter bees (Megachilidae spp.) cut circular sections from the leaf margins, sometimes removing most of the leaf.[11]

A vintage use of pondberry fruit in the rural South was as projectiles in toy pop guns constructed by children from hollowed-out elderberry (Sambucus canadensis) stems.[14][15]

A large part of pondberry habitat disappeared when forests were cut for timber or for conversion to agricultural fields, and as wetlands were drained. In some cases, wetlands were permanently flooded to construct lakes. Many of the existing colonies of pondberry are small, and occupy only a portion of the apparently suitable habitat.

There are indications that pondberry, which is in the Laurel family, is susceptible to laurel wilt (Raffaelea lauricola).[16] This fungal disease is introduced into host plants by a non-native insect, the redbay ambrosia beetle (Xyleborus glabratus) and kills the plant by plugging the water-conducting cells of the afflicted individual, causing it to wilt and eventually die. There is no known cure for this disease, which has quickly spread through other members of the laurel family (especially redbay, Persia borbonia) from the coast of South Carolina inland towards the native habitat of pondberry.

Pondberry was listed as endangered in 1986. The U.S. Fish and Wildlife Service's restoration plan states: existing pondberry populations should be protected from forestry and agricultural management actions and protected from grazing and browsing animals; searches for new populations should be continued; areas where pondberry has not been located but provide suitable habitat should be protected; and, new populations should be established or reestablish extirpated populations at suitable sites.[2]

A critical part of the restoration effort is to increase the knowledge about pondberry's ecology and reproduction.[7] A team of researchers from the U.S. Forest Service's Southern Research Station are working with the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service to learn as much as they can about the biology and ecology of pondberry. Scientists are investigating the role of flooding and light availability on pondberry at a large-scale impoundment facility, and they have set up controlled experiments to study competition, seed germination, seed storage, and seed persistence in the soil seed bank. An integrated approach is being used to learn more about pondberry's ecology, insect predators, fungal pathogens, physiological responses to light availability and flooding, population genetics, seed physiology, and seed dispersal.